What is said when a situation or conversation can not get any more awkward.

Nuclear is just irrelevant and Cream could be suggesting many things which allows for the other's mind to wander and wonder leaving room for vague awkward silence. "Cream" may entail the white inside of an oreo or even jizz. Once "nuclear cream" is said, there is no going back to times before awkward small talk.

Friend B: So, how was it? Was it ok?
Friend A: Well, it was a bit painful because, well, you know...the stretch...
Friend B: ..........what?
Friend A: Wait, what are we talking about again?
Friend B: How you told your parents about being gay..?
Friend A: OH! Sorry, I thought we were talking about the time I lost my virginity.
Friend B:..Nuclear Cream.